Depending on the intended use for the AME fixtures at Southland, they are fitted with external surface-mounted hydraulics and with internally cored hydraulics.
Southland CNC of Cornelia, Georgia, a Tier Two supplier to the automotive industry, provides machined components to all three American and the six largest foreign auto manufacturers.
The 13-year old company has grown from a single machine in President/Owner Keith Armour’s garage to a facility with 21 highcapacity machining centers.
Southland machines a mix of parts that includes high-volume and lowvolume production runs. The company uses dedicated hydraulic clamping fixtures for its high-volume production runs because those fixtures decrease production time and make the fixturing cost-effective. The dedicated hydraulic fixtures also provide consistent and repeatable clamping pressure that results in improved machining accuracy.
Because low-volume production runs do not justify dedicated fixturing, Southland CNC uses manual fixturing for those applications.
Southland has four horizontal machining centers and three vertical machining centers that use hydraulic tombstone fixturing designed and built by Advanced Machine and Engineering (AME) (www.ame.com). These fixtures are dedicated to high-volume production of single parts or single families of parts.
Southland chose Advanced Machine and Engineering to provide its first tombstone hydraulic fixture because Advanced Machine and Engineering’s fixturing was competitively priced and specifically designed by its engineers to fit Southland’s production needs. Delivery, which is important to Southland’s production scheduling, was better than other suppliers.
The first Advanced Machine and Engineering fixture replaced customersupplied fixturing that Southland had been using and that Southland believed was not providing the efficiency needed to meet its cost and schedule goals for high-volume production runs.
The advantages provided by the fixture that Advanced Machine and Engineering designed included reduced load and unload time, reduced cycle time, reduced scrap rates and error-free loading. The first time that Southland used the fixture, it reduced cycle time by nearly 40 percent, allowing Southland to produce its high production volumes to schedule without other machines.
The fixture has an automatic clamp and release, and locating dowels to ensure error-free handling.
Each part to be machined is handled only as it is loaded into the fixture, and when it is unloaded. Because the fixture is a windowed fixture, the component is completely machined on all four sides without additional handling.
Armour said the Advanced Machine and Engineering fixturing has been reliable. One fixture has been in operation 20 hours a day, five days a week for more than two years without a problem.
Because of that reliability, and because of the cooperation and innovation Advanced Machine and Engineering has provided, Southland added fixtures that are used on its vertical machining centers and one dedicated to its horizontal machines.
The fixture configurations designed for Southland include cast tombstones and welded tombstones.